Reenforced and leak-tight paper box



ne 28 1927. Ju E. w. LABOMBARDE REENFORCED AND LEAK TIGHT PAPER BOX Filed' Maron :15. 1924 A THW/Vix Patented June 28, v1,927.

PATENT OFFICE.

ELIE W. LABOMBARDE, OF NASHUA, NEW HAMPSHIRE REENFOBCED AND LEAK-TIGHT PAPER BOX.

Application led March 18, 1924. Serial No. 898,905.

This invention relates to paper boxes and has particular reference to the production of boxes having no cornery openings through which comminuted material can escape or through'which the dampness of moist air,

or insects or germs, can gain access to the space, as well as for `cheapness and rapidity.

of production by automatic machinery, it is customary to employ the type of *boxes known as folding boxes or cartons which .can be shipped and stored flat andvthen opened or set up'for filling. They usually include eight flaps (four for the bottom and four forthe top) and the slits or cuts which deline the, edges of said flaps extend into those portions which constitute the eight corners of the box. When such a box is set up, and lled, `and the aps folded in to close the box', there is asmall hole, frequently referred to as a pin hole, at the inner end of each slit. Consequently, unless something is provided to obstruct these holes at the corners of the box, moisture or germs or small insects can enter, and finely comminuted material is liable to escape. So far as l am aware, the only obstruction heretofore found practicable for the holes has consisted of paper wrappers or wax paper linings. Suchk wrappers or linings are usually of parained paper when the boxes contain something whichwould be affected ,by

moisture. The use of such wrappers or lin-` ings adds materially to the expense which expense is, of course, eventually borne by the consumers of the goods.

An'important feature of my invention consists in the provision of flexible tear-resisting corner reenforcements which are .lightly and uniformly secured t'o the blanks and traverse the inner ends of the flap-defining slits and, after the box is filled, are folded with the flaps so as to not only strengthen the corners of the box but also effectively bar egress of any of the contents of the box no matter how finely-comminuted it may be, and also prevent ingress of moisture, insects, or germs. This renders unnecessary the employment of any kind of outside wrapper, and enables the usual atployed in tractive printing, or directions, on the outside ofthe box to be seen without the cloudy effect produced when paratiined paper lwrappings are employed.

'lhe object of lightly but uniformly securing the reenforcements, adhesively, to the blanks, and the advantages thereof, will be explained hereinafter.

Preferably the reeinforcements are .ap4 plied in the form of strips to that surface of the blank which is inside when the blank is folded to box form, but in any event-such strips are applied to the blanks before they are converted to box form because, if applied after the box is made u and filled, the applying of the strips woul either have to be effected inanlially or by the independent operation of rather expensive mechanisin.- Under my invention, the strips can be applied by the machine which folds-'the blanks to fiat form for shipment to.those whoA are to fill the boxes.

In the accompanying drawings I' have illustrated my .invention as applied to, or `in connection with, a ,well known form of box now commoniy used for containing sugar, said form being also used for other goods. It is but one of several forms of boxes in which the present invention may be embodied.

Of the drawings v Figure l is a plan View of the said ordinary blank alone. l'

Figure2 is a plan view of the blank with the strips aliixed thereto. i

Figure 3 represents a section on line 3-3 of Figure 2 on an exaggerated scale.

Figures 4 and successive steps of closing either end of the box.

N umerals are employed to designate the different portions of the blank, and letters to indicate my improvements.

The material of which the blankis made is cut and creased to form wall sections l2, 13, 14, 15, a narrow strip 16 which is to be adhesively secured to the margin of the section 12 by the usual-folding machine, and flaps 17, 18, 19 and 20 at the end of the wall sections. Said flaps are fold-able in the usual manner to close 'the ends of the box. When the boxis to be used for containing comminuted material it is customary to refer to one end as the bottom and the other end as the to Automatic machines .are emarge plants, which machines fir* -5 are views to illustrate' fold and seal the bottom flaps, then fill through the still open upper end, and then fold and seal the flaps Kat the top. The

folding and sealing is the same at each end, viz: the flaps 17 19, are folded in until their end edges meet or (as is usual) slightly overlap, then while the flaps 18, 20, are held spread apart glue is applied to those surfaces which are then uppermost, then the flap 18 is folded onto the flaps 17 19, nd finally the flap 20 is folded onto the Xs so far described, the blank and the method of folding it, and filling and closing it, are well known. My improvements require no change in the blank itself so far as its shape is concerned, and re uire no change in the method ofl folding, fil ing and closing and sealing.

In carrying out my invention I affix to each blank, along and covering the two crease lines 21 on which the iaps are folded, strips a of strong flexible material such as .Kraft paper, which material, as is wellknown, is tougher and more wear-resisting than the kind of card board customarily employed for the blanks of boxes. This is easily effected while the blanks are fiat as inV Figure 1, by automatic machinery, so as to but slightly increase the cost of the reenforced blanks. It may be done while the bare blanks are on their way from a feeder to the usual mechanism which produces the flat folded cartons to be shipped to users or To enable the flaps to be closed successively in the usual order as hereinbefore described, without tearing the strips, said strips are held in position on the blanks by means of an adhesive (hereinafter referred to generically as glue) of a character which, whlle strong enough to prevent the strips from shifting out of position, is weak enough to hold the strips so lightly to the blank that when the flaps are closed down portions of the strips will pull away from the blank to enable portions of the strips to be doubled and interfolded with the aps and result in the formation of packings at the corners ofthe boxes. Sometlmes it is desirable that the strips shall be entirely free from the blanks along the crease lines 21. Therefore the mechanism which applies the glue for afxling each strip a is arranged to cause adher crease line 21 by permitting it to flatten out.

It has been proposed to aflix somewhat analogous strips to blanks by means of glue applied to some areas and not to others, but this necessitates the employment of gluing devices havin a certain pattern. Such devices add to t e expense of production and tend to reduce speed of production. And a more important objection is that whenever different shapes or sizes of blanks are to be provided with the reenforcing strips, changes must be made in the particular pattern or style of glue applying devlces. Under my invention, including the employment of a weak glue which will enable any portions of the strips to be pulled away from the blanks without tearing or mutilation of either, the gluing devices may comprise the ordinary glue disks or wheels having uniform peripheries such as are commonly employed in boX making machinery.

The result of weakly but uniformly securing the strips is that when the fiaps 17 19, are folded 1n (see flap 17 in Fig. 4) such portions of the strip as indicated at 'a2 will be pulled away from the blank without tearing the strip but only doubling it.

The folding in of the two iaps 17, 19, after the set up box has been lled, carries with the flaps those portions of the strip a which extend across said iaps and away .the portions la? and doubles or olds them as indicated in Figure 5 because other portions of the strip are held supported by the flaps 18., 20. Then the iiap 18 the inner surface ofwhich is, in practice, preliminarily coated with glue, is folded onto the tops ticed. But by the interposition of the strips.

htly secured and folded substantially escribed, the crease'lines of the box at top and bottom are. reenforced and, most important of all, the corners of the box can have no holes through which anything deleterious can pass.

As indicated in Figure 3, the strip a is creased in line with the blank crease 21. Such creasing of the strip may be effected before applying the=strip,'or after. By such creasing of the strip liability of tearing at the corners of the box when the flaps are folded in is reduced. It 'also facilitates proper folding of the flaps on the crease lines 21.

Thestrips a even when continuous from end to end as is preferred, do not interfere with the flaps being heldup during a filling operation conducted in the same manner as is customary. During filling there is no need for the flaps tobe swung outwardly. After filling, and after the flaps 17, 19, are folded a li l ing of the iaps 18, 20, to enable their then upper surfaces to be coated with glue in the same manner as now practiced. In brief, the presence of the strips a interferes in no way with the present practice of converting the atfolded 4cartons to open condition an then closing the bottom flaps, depositing goods, and then closing the to flaps. The strips are applied to the bla while the latter are flat and therefore add but slightly to the cost thereof. And they cause no increase whatever in the time required for packaging goods because they not only ermit conversion of the blanks to fiat fo ded form for shi ment in the same manner as no'vv 7practice but also require no variation whatever in the present methods of setting up, filling, and closin and sealing. In fact for many classes o goods, "expenses and time are reduced because no outside wrappers are necessary to ensure integrityv of the contents of the boxes and therefore' no wrapping machines are needed. l

It will now be understood that blanks or boxes made according to myv invention are4 characterized -by tough tear-resisting reenforcing orleak-stoppmg material adhesively axixed by glue which 1s weaker than said material so that any tendency or eortto separate the said reenforcin material from' the blank or'. box will pull t e said material away without tearing it and without any liability of causing any holes to appear at the corners of the box.

Having now described my invention, I claimz` A A paper box blankcut and creased to provide foldable flaps and having -strips of tou h tear-resisting reenforcing material extending across the crease lines of the flaps, the entire areas of said strips lbeing lightly glued' to the blank whereb any portions of said strips may be .pulled7 away from the blank without tearing the vblank or the strips.

In testimony. whereof I have aixed my signature. Y

ELIEW. LABQimaRDE. 

